|
Hydrodesulfurization (HDS) is a catalytic chemical process widely used to remove sulfur (S) from natural gas and from refined petroleum products, such as gasoline or petrol, jet fuel, kerosene, diesel fuel, and fuel oils.〔(''Hydrodesulfurization Technologies and Costs'' ) Nancy Yamaguchi, Trans Energy Associates, William and Flora Hewlett Foundation Sulfur Workshop, Mexico City, May 29–30, 2003〕 The purpose of removing the sulfur is to reduce the sulfur dioxide () emissions that result from using those fuels in automotive vehicles, aircraft, railroad locomotives, ships, gas or oil burning power plants, residential and industrial furnaces, and other forms of fuel combustion. Another important reason for removing sulfur from the naphtha streams within a petroleum refinery is that sulfur, even in extremely low concentrations, poisons the noble metal catalysts (platinum and rhenium) in the catalytic reforming units that are subsequently used to upgrade the octane rating of the naphtha streams. The industrial hydrodesulfurization processes include facilities for the capture and removal of the resulting hydrogen sulfide () gas. In petroleum refineries, the hydrogen sulfide gas is then subsequently converted into byproduct elemental sulfur or sulfuric acid (). In fact, the vast majority of the 64,000,000 metric tons of sulfur produced worldwide in 2005 was byproduct sulfur from refineries and other hydrocarbon processing plants.〔(Sulfur production report ) by the United States Geological Survey〕〔(Discussion of recovered byproduct sulfur )〕 An HDS unit in the petroleum refining industry is also often referred to as a hydrotreater. ==History== Although some reactions involving catalytic hydrogenation of organic substances were already known, the property of finely divided nickel to catalyze the fixation of hydrogen on hydrocarbon (ethylene, benzene) double bonds was discovered by the French chemist Paul Sabatier in 1897.〔C.R.Acad.Sci. 1897, 132, 210〕〔C.R.Acad.Sci. 1901, 132, 210〕 Through this work, he found that unsaturated hydrocarbons in the vapor phase could be converted into saturated hydrocarbons by using hydrogen and a catalytic metal, laying the foundation of the modern catalytic hydrogenation process. Soon after Sabatier's work, a German chemist, Wilhelm Normann, found that catalytic hydrogenation could be used to convert unsaturated fatty acids or glycerides in the liquid phase into saturated ones. He was awarded a patent in Germany in 1902〔(DE Patent DE141029 (Espacenet, record not available) )〕 and in Britain in 1903,〔(UK Patent GB190301515 GB190301515 (Espacenet) )〕 which was the beginning of what is now a worldwide industry. In the mid-1950s, the first noble metal catalytic reforming process (the Platformer process) was commercialized. At the same time, the catalytic hydrodesulfurization of the naphtha feed to such reformers was also commercialized. In the decades that followed, various proprietary catalytic hydrodesulfurization processes, such as the one depicted in the flow diagram below, have been commercialized. Currently, virtually all of the petroleum refineries worldwide have one or more HDS units. By 2006, miniature microfluidic HDS units had been implemented for treating JP-8 jet fuel to produce clean feed stock for a fuel cell hydrogen reformer.〔(Microchannel HDS (March 2006) )〕 By 2007, this had been integrated into an operating 5 kW fuel cell generation system.〔(Fuel cells help make noisy, hot generators a thing of the past (December 2007) Pacific Northwest National Laboratory )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「hydrodesulfurization」の詳細全文を読む スポンサード リンク
|